From left, Britain's Prince Harry, British Prime Minister David Cameron, Kate, Duchess of Cambridge, Belgium's King Philippe, Belgium's Queen Mathilde and Britain's Prince William attend a commemoration ceremony to mark the 100th anniversary of the outbreak of World War I at the St. Symphorien Cemetery in St. Symphorien, Belgium on Monday, Aug. 4, 2014. The cemetery was established by the German Army as a final resting place for British and German soldiers killed at the Battle of Mons. Among those buried is Pvt. John Parr of the Middlesex Regiment, the first British soldier to be killed in action on the Western Front. (AP Photo/Virginia Mayo) ( Belgium World War I Commemoration )